This invention relates to automated server replication.
The popularity of the World Wide Web as a communications medium lies in the richness of its information content and ease of use. Information in this medium exists as objects in a widely distributed collection of internetworked servers, each object uniquely addressable by its own Uniform Resource Locator (URL). The proliferation of commercial applications on the World Wide Web brings with it an increasing number of users making ever-increasing numbers of requests for web content. The problems of latency and bandwidth considerations manifest themselves in delay and lost information.
Network architects respond using an array of solutions, one of which is the server farm. This involves the use of multiple web servers with identical content, or the segmentation based upon functionality. For example, two servers for web functions, two for File Transfer Protocol (FTP), two as a database, and so forth. The use of multiple servers solves one problem at the expense of creating another. If there are multiple servers, how does the end user locate a particular web site? Presently, names and Universal Resource Locator (URLs) are resolved into unique single addresses by a Domain Name Service (DNS) residing in a DNS server. DNS servers maintain a list of domain names cross referenced to individual Internet Protocol (IP) addresses. However, if multiple web servers or server farms are used, a modified version of DNS service is used. A common approach to this problem is to modify the DNS system to be aware of a one-to-many mapping of names-to-IP-addresses. Thus, the DNS will return an IP address that comes from a list of possible IP addresses that correspond to a particular web object. Thus, from one moment to the next, a DNS query will resolve to different IP addresses. In this example, the modified DNS decides which IP address to return based on how busy each of the servers is.
In current network management systems, there are various methods of detecting and monitoring the load across a server or a server farm. One system uses a load capacity detection agent to monitor the load across a server or a server farm. In this system, when the load detection agent detects that a server farm, for example, is experiencing excess load, the agent notifies a system administrator of the system. The system administrator may decide to manually take action to either reduce the load across the server farm, or alternatively, increase the available load capacity by adding a server to the server farm. Generally, the system administrator adds a server by manually identifying an additional available server, and then modifying the entries in the load management system to include the IP address of the recently-added content server.